1. Field of the Invention
The present invention relates generally to antennas. More particularly, the present invention relates to antenna apparatuses for vehicles.
2. Description of the Related Art
Certain conventional apparatuses unlock vehicular doors using radio waves. Some keyless entry apparatuses of this type have an exclusive antenna that is set, for example, on the rear window glass and a receiving circuit arranged within the trunk in order to increase the signal receiving sensitivity. The receiving circuit and the antenna are connected through a coaxial cable. One implementation of this type of arrangement is disclosed in unexamined Japanese Utility Model Publication No. H4-86382.
In some implementations, however, a coaxial cable is used to connect the receiving circuit and the antenna. Such implementations also require a connector exclusive for the coaxial cable, a case for accommodating the receiving circuit, and a power source line for supplying radio waves to the receiving circuit. These additional components can significantly increase the cost of the keyless entry system.